Question about 68 Classic Automag Bolt Spring

So got my hands on a 68 Classic in really nice shape except for one significant issue. The spring was completely rusted. Glad I broke it down before shooting it. My question, Is there a difference in the springs between different versions of automags? I've searched various places and can't seem to find an answer. Just want to make sure if I buy a replacement spring on eBay it's going to work.

I find it funny that this was the biggest stigma against Autocockers when they were still big so WGP after budd sold the company decided to come out with an Autococker that didn't need to be timed called the Trilogy In order to get a more "user friendly" Autococker out to the masses. Once they were released everyone was like "This marker sucks! You can't even time it!"

These are the three springs that "could" be in your Mag. They're $4 a piece, at the time I write this, from AGD, plus shipping. If you have a level 7 bolt, you want the bottom spring. If you have a level 10 bolt, it could be anyone of those three. I would suggest buying one of these springs instead of trying to remove the rust. Unless you don't have the time to wait for a shipment to come in.